140 



KNOWLEDGE. 



[June 1, 1899. 



the fallen segments of wbicli, after they have been chewed 

 by the crab, cover the ground." Mr. C. Hedley (in 

 Whitelegge's "Crustacea of Funafuti," Sydney, 1897) 

 observes that as " the cocoanut is foreign to the native 

 flora, and of comparatively recent introduction from abroad, 

 it follows that the taste for this nut has been acquired in 

 historical times by Biripis, whose original food was probably 

 Pandanus fruit." Major Alcock (" A Summary of the 

 Deep-Sea Work of the hu-cstir/<itor, 1899 ") recalls to mind 

 Sir Francis Drake's report of certain desirable oriental 

 crabs that " for want of other refuge, when we came to 

 take them, did climb up into trees to hide themselves, 

 whither we were enforced to climb after them." For 

 additional proof that this was no mere traveller's tale, Mr. 

 C. W. Andrews, in his recent visit to Christmas Island, 

 brought the camera to bear on the question, and photo- 

 graphed a crab in a tree-top, and a crab in the act of 

 climbing a tree. 



Mr. Gardiner, again quoted by Mr. Borradaile, gives the 

 following interesting account of the domesticity of a species 

 in a quite different group of crustaceans. The LysiosqtdUa 

 maculata (Fabr.) is found, he says, in the boat channel at 

 Rotuma. " It lives in pairs in tunnels on the sandy 

 bottom. These are sometimes as much as twenty feet 

 long, and usually have two exit holes. Each hole is 

 inhabited by a male and a female, which take up their 

 positions at the two exits, with the dactyhts and propodite 

 of the raptorial claw widely extended, and just projecting. 

 Any small fish passing over is seized, and the animal 

 retreats with it into its tunnel." Such then is a hunting 

 lodge, as employed by some of the rapacious and strongly 

 armoured Squillida?. Similar tunnels are used, no doubt 

 for similar freebooting purposes, by various more or less 

 prawn-like animals, such as Upogebia and Callianassa, 

 of which specimens are occasionally found on our own 

 coasts. The Callianassa has an additional reason for hiding 

 in a sub-aquatic tunnel, in that it is a very soft-bodied 

 animal. It is of singular appearance because of the size 

 and strength exhibited by the terminal joints of a single 

 claw. A strange crustacean, nearly allied to the two 

 genera just mentioned, is the Thalassitui anonialus, and Dr. 

 J. Anderson gives a strange account of its dwelling-place. 

 The notice occurs in his description of the reptiles of the 

 Mergui Archipelago {Jour. Linn. Soc. Loiid., Vol. XXI., 

 p. Sii, 1889). Where a lizard was common in a swamp, at 

 the mouth of a small freshwater stream, there, among the 

 palms, the crustacean " had thrown up the great mud 

 mounds that occur over its underground chambers. They 

 were strewn with the fallen leaves of the palm, and were 

 more or less riddled with holes made by the crustacean, 

 the eminences being converted into islets at high tide." 



On the river-crabs that by the winding streamlet, 

 beneath the roots of large umbrageous trees, construct their 

 burrows, and that sit at the entrances with one eye on the 

 romantic scenery around them and the other on any sus- 

 picious-looking tourist passing by, there is not time to 

 dilate as they deserve. A cursory hint must suffice for the 

 Drowia, which, with singular coolness and inflexible 

 tenacity, embeds itself in a colony of compound ascidians, 

 and for the miscellaneous crustaceans which in early life 

 find their way into the glassy network of a Venus's Flower 

 Basket, destined, it would seem, to live and die in that 

 graceful enclosure. The crowd of crabs and shrimps and 

 cumaceans and isopods and amphipods which simply bury 

 themselves for protection in the sand from time to time at 

 any convenient spot, can scarcely be said to have homes. 

 In their case the facility of change, the absence of all local 

 obligation or of any need to think about repairs, must 

 destroy the very idea of a house. But this happy-go-lucky 



freedom from care is not shared by all even of the small 

 Crustacea. Those which, like the isopod known as the 

 Gribble, and the amphipod called Chelura teirhrans, bore 

 into submerged timber, have indeed, a sort of home, though 

 they are continually changing it ; but the change is made 

 by almost imperceptible degrees and on very easy terms, 

 since it appears that they only leave one chamber because 

 they are eating their way into the next. Some amphipods, 

 however, construct tubes, either free or attached, by help 

 of a glandular secretion, which issues through a tiny aper- 

 ture in some of their toes. This becomes a firm cement, 

 and the structure is often consolidated still further by 

 interwoven bits of seaweed, fragments of shell, grains of 

 sand, and other contributories. Pity would be wasted on 

 the cramped area of the lodging, since 

 ^:: it is always ample for the lodger. 

 An instance of this is afforded by 

 Mr. Robert Templeton's account of a 

 little tubicolous amphipod which he 

 picked up "at Mauritius, or on the 

 way thither, " between sixty and 

 seventy years ago. " While watching 

 it," he says, " which I did for some 

 hours, I was exceedingly surprised 

 and amused to find it disappearing 

 from one end of the tube, and reap- 

 pearing like magic at the other, 

 having doubled itself up towards its 

 belly in the passage, but with such 

 quickness, considering the narrow 

 calibre of its mansion, that I could 

 hardly credit my eyes but that it 

 had two heads, and, indeed, a gen- 

 tleman who was with me in the 

 pavilion at the time could not be 

 persuaded to the contrary. The 

 animal, however, scarcely remained a 

 second at this extremity, but shot 

 back to the one it had formerly oc- 

 cupied ; and during the time I 

 watched it I never saw it remain permanently at it, or 

 rather, I should say, for a longer period than a second, or 

 a second and a half at furthest." So independent is real 

 energy of the narrowness of the sphere in which it works. 



Cerapus ahdiius 

 Tcinpletou, emerging 

 from its tube. From 

 Templeton. 



By John H. Cooke, f.l.s., p.g.s. 



In biological laboratories, where the microtome is in constant 

 use, it is of importance that the edges of the microtome knives 

 should be kept in as perfect a condition as possible. To prevent 

 dulling of the edge, which results from oxidation, the knives 

 should be kept immersed in a one per cent, solution of carbonate 

 of sodium. This treatment will not only prevent them rusting, 

 but will also render them perfectly asceptic. 



Dr. Buchner's recent discovery that the alcoholic fermentation 

 set up by the yeast plant, is due to the chemical power of an 

 amyloyte acting in a manner similar to . digestive ferment, 

 caused a sensation among those who had hitherto held that the 

 action of yeast could not be dissociated from the living plant. 

 To demonstrate the action of this ferment, the yeast cells should 

 be thoroughly disrupted by grinding them up with quartz sand, 

 and, subsequently, submitted to a pressure of about five hundred 

 atmospheres. Some few cells may escape destruction in this 

 process, and these should be searched for with the microscope, 

 and either disrupted or removed. The resultant powdered 

 mass will act similarly to untreated yeast, thus showing that 

 the fermentative action hitherto attributed to the living cell is, 

 in reality, due to a fermentative enzj-me. 



The nucleus of the malarial parasite has been demonstrated 

 by Ziemann with the aid of a new stain, consisting of a mixture 



